What to do if my Apple Watch Ultra 2 Action Button fails after watchOS 26 update?

Anyone experiencing issues with the latest OS26 and the Apple Watch Ultra 2? After upgrading my watch, it went completely haywire overnight. The siren kept going off, and the action button didn’t work at all. I had to force it off manually. I tried unpairing it, resetting it, turning off the action button and starting fresh, but the problem persisted. The action button would engage without any touch, and the screens would cycle between the workout app, SOS screen, and randomly turning off. Also the side button doesn't work. Only forcing restart are the only action I can manually engage. It’s completely frustrating. I called Apple support, and the representative suggested that my Action button might be stuck, causing all this trouble. However, I informed him that the watch was functioning perfectly before the OS upgrade. His recommendation was to repair it for $400, which I declined. It’s absurd that the watch would malfunction after the OS upgrade and Apple wants me to repair the hardware.

I’m curious if anyone else is experiencing similar issues and has any advice. Thanks in advance.

[Re-Titled by Moderator]

Original Title: Watch OS26 and action button Ultra V2 going crazy